In a letter, President Jeffrey Armstrong described the behavior as “deplorable” and promised the university will seek ways to promote diversity and cultural sensitivity on the predominantly white campus. But because no campus policy was violated, those responsible will not be punished.

It should. Five years ago, then President Warren Baker made a similar statement in response to an outrageous Halloween display at Crops House — an on-campus residence for agriculture students — of a noose, Confederate flag and sign with derogatory language toward blacks, gays and hippies.

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“I am outraged and saddened by this,” Baker told a gathering of hundreds of students and residents.

While the responsible students weren’t punished — attorneys advised that the display was protected by the First Amendment — Baker and other Poly officials also said they were looking at ways to improve tolerance and acceptance of minority students on campus and in the San Luis Obispo community.

Several steps have been taken, including the hiring of an ombudsperson and establishment of an office of inclusivity and diversity.

Also, all students are required to take at least one course that covers issues relating to cultural pluralism, and a specialist has been hired to advise on how to incorporate diversity and inclusivity into other courses.

Also, in January, a mandate will kick in that requires fraternities and sororities to register in advance if they intend to have a party. They’ll be required to provide information on the size of the party and the theme — and that will give the university an opportunity to counsel students if the theme is offensive.

Cal Poly also is actively trying to recruit more minority students. Given the university’s demographics — 61 percent of students are white, 14 percent Hispanic, 12 percent Asian, 6 percent biracial and 1 percent are black — that must be a priority but as pointed out in today’s Viewpoint, such recruitment efforts can be seriously undermined by incidents such as this one.

It’s unfortunate that an insensitive move by a small number of students can have such a negative ripple effect, but that’s the reality that Cal Poly must face.

We recognize that Cal Poly can’t be held responsible for the attitudes and behavior of its students, and we agree that it’s tough to legislate common decency. And yes, students have the right to free speech — however objectionable and insensitive that speech may be.

At the same time, we expect Cal Poly to do everything in its power to provide a safe and welcoming environment for all students. Otherwise, we’ll be going through the same hand-wringing five years from now, and five years after that.

What more can be done? That should become clearer following a student survey that will be conducted in February. The survey is expected to provide base line data on student perceptions of race, gender and other diversity issues. Results are due in the fall. We look forward to that.